When a cancer cell throws out its trash, it can turn healthy neighbors into fellow tumor cells, researchers have found.

Many cells, including cancerous ones, shed thousands of tiny
membrane-bound vesicles called exosomes that contain proteins, DNA and
RNA. The process is thought to be a waste-management system, but it may
also facilitate cell-to-cell communication: some of these vesicles can
then merge with other cells and dump their payload inside.

In a study published online on October 23 in Cancer Cell,
researchers show that when human breast-cancer exosomes can cause tumors
when mixed with normal cells then injected into mice. The results could
pave the way to finding markers to monitor the progression of cancer,
and possibly even point to targets for therapies.

“It’s amazing — these vesicles were considered garbage cans,” says
Khalid Al-Nedawi, a cancer researcher at McMaster University in
Hamilton, Canada. “This paper really brings us closer to harnessing the
potential of these tiny vesicles.”